Battery packs provide power for various technologies ranging from portable electronics to renewable power systems and environmentally friendly vehicles. For example, hybrid electric vehicles (HEV) use a battery pack and an electric motor in conjunction with a combustion engine to increase fuel efficiency. Battery packs are formed of a plurality of battery modules, where each battery module includes several electrochemical cells. Within the battery modules, the cells are arranged in two or three dimensional arrays and are electrically connected in series or in parallel. Likewise, the battery modules within a battery pack are electrically connected in series or in parallel.